386 Surgical Diseases and Surgery of the Dog 



(1) TrvLe Cysts- 



(0) Retention and Gland Cysts. .. .Hydronephrosis, Hydro- 



cholecyst, Ranula, Chy- 

 lecysts, Ovarial, Uterine. 

 Mammary, Sebacepus, 

 ' and Mucous cysts. 



(&) Tubulo-Cysts Cystic tumors associated 



with remnants of the 

 Ducts of the Fetal Mes- 

 onephros. 



(c) Hydrocele Of the Tunica Vaginalis 



Testis. 



(2) Pseudo-Cysts. 



(a) Bursae ;....... Synovial, etc. 



(b) Contusion and Extravasation Cysts . . . .Hematomata, etc. 



(c) Neural Cysts ..Hydrocephalus and Hydrocele of Ventricles 



(d) Parasitic Cysts , Hydatids 



(e) Emphysematous Cysts Of the Mesentery 



(/) Degeneration Cysts Of solid Tumors 



(1) True Cysts. 



(a) Betention and Gland Cysts are formed by accumula- 

 tions of fluid which is hindered from escaping by some obstruction. 

 Should the condition persist, the glandular tissue undergoes pres- 

 ure-atrophy and finally the gland and its duct become converted into 

 a cyst, the contents of which are usually of a brownish-yellow color. 

 The condition known as Hydronephrosis is due to dilation of the 

 pelvis and infundibula of the kidney as a result of intra- or extra- 

 mural obstruction in some part of the urinary tract. If the obstruc- 

 tion occur in the Ureter from tumor, calculi, etc., or at its vesical 

 orifice, there is a unilateral accumulation, but if it occur at the Neck 

 of the Bladder or in the Urethra from enlarged prostate or impacted 

 calculus, the condition becomes bilateral. Unilateral hydronephrosis 

 does not necessarily exert a baneful effect on the health of the ani- 

 mal, the remaining kidney taking on the function of its defunct fel- 

 low, but bilateral hydronephrosis is speedily lethal through non- 

 elimination of urine. The condition has been observed bv Roell, 



